The automatic settings, enabled by default when Pulse Building starts up, allow the system to select default values automatically based on signal properties and the current system hardware.
The signal bandwidth parameter serves two purposes: The first is to set the bandwidth of the test signal (see Play Test Signal). The second is to help optimize signal corrections.
A check in this box enables Pulse Building to set the signal correction bandwidth automatically to the maximum signal bandwidth based on the current signal properties and the system hardware capabilities. This value is the smaller of 80% of the current sample rate or the actual hardware bandwidth. This allows easy sharing of Pulse Building setting files across hardware platforms. When you disable the automatic setting, you must set the signal correction bandwidth manually.
When setting the signal bandwidth manually, set the value to the maximum RF bandwidth of your signal. The maximum bandwidth of your signal is dependent on any intra-pulse modulation and any frequency offsets specified in the Signal Pattern. The signal bandwidth should typically be < 0.8 × (Sampling Rate).
Range: 10 MHz to 1100 MHz (determined by the hardware configuration)
Internal I/Q default: 80 MHz
External I/Q default: 240 MHz
Wideband I/Q default: 1000 MHz
The Signal Bandwidth default value is 1000 MHz when the system is configured for wideband using either an N603xA/M933xA or N824xA Arb. If the Arb has a maximum sample rate of 625 MHz, the Signal Bandwidth is 500 MHz.
A check in this box enables Pulse Building to calculate the waveform RMS voltage automatically. The signal generator uses this value when executing a power search during a Play when its ALC is disabled. This value provides accurate output power when the ALC is disabled. See Getting Correct Output Power for more information.
Uncheck the box to enter the RMS voltage manually. A value derived from this starting point is used by the signal generator as the power search reference level when the ALC is turned off. The value entered here is not directly entered into the signal generator Power Search Manual voltage. It is scaled by any corrections and re-scaling that occurs in the Pulse Building application.
Pulse Building does not directly control the Baseband Filter and Modulator Attenuation properties for the source. The source firmware has been optimized to set the modulator attenuator value based on the waveform RMS voltage. You may override this feature by manually setting the modulator attenuator value in the source from the front panel or with SCPI commands. Baseband Filter and Modulator Attenuator discusses these properties.